Intel® Quartus® Prime Pro Edition User Guide: Design Optimization

ID 683641
Date 10/04/2021

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5.5.3. View Timing Optimization Advisor

While the Timing Analyzer Report Timing Closure Recommendations task gives specific recommendations to fix failing paths, the Timing Optimization Advisor gives more general recommendations to improve timing performance for a design.

The Timing Optimization Advisor guides you in making settings that optimize your design to meet your timing requirements. To run the Timing Optimization Advisor click Tools > Advisors > Timing Optimization Advisor. This advisor describes many of the suggestions made in this section.

When you open the Timing Optimization Advisor after compilation, you can find recommendations to improve the timing performance of your design. If suggestions in these advisors contradict each other, evaluate these options and choose the settings that best suit the given requirements.

The example shows the Timing Optimization Advisor after compiling a design that meets its frequency requirements, but requires setting changes to improve the timing.

Figure 24. Timing Optimization Advisor

When you expand one of the categories in the Timing Optimization Advisor, such as Maximum Frequency (fmax) or I/O Timing (tsu, tco, tpd), the recommendations appear in stages. These stages show the order in which to apply the recommended settings.

The first stage contains the options that are easiest to change, make the least drastic changes to your design optimization, and have the least effect on compilation time.

Icons indicate whether each recommended setting has been made in the current project. In the figure, the checkmark icons in the list of recommendations for Stage 1 indicates recommendations that are already implemented. The warning icons indicate recommendations that are not followed for this compilation. The information icons indicate general suggestions. For these entries, the advisor does not report whether these recommendations were followed, but instead explains how you can achieve better performance. For a legend that provides more information for each icon, refer to the “How to use” page in the Timing Optimization Advisor.

Each recommendation provides a link to the appropriate location in the Intel® Quartus® Prime GUI where you can change the settings. For example, consider the Synthesis Netlist Optimizations page of the Settings dialog box or the Global Signals category in the Assignment Editor. This approach provides the most control over which settings are made and helps you learn about the settings in the software. When available, you can also use the Correct the Settings button to automatically make the suggested change to global settings.

For some entries in the Timing Optimization Advisor, a button allows you to further analyze your design and see more information. The advisor provides a table with the clocks in the design, indicating whether they have been assigned a timing constraint.